package com.campus.counseling.handler;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

@MappedJdbcTypes(JdbcType.VARCHAR)
@MappedTypes(List.class)
public class ListTypeHandler extends BaseTypeHandler<List<String>> {
    
    private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();

    @Override
    public void setNonNullParameter(PreparedStatement ps, int i, List<String> parameter, JdbcType jdbcType) throws SQLException {
        String jsonStr = null;
        try {
            jsonStr = OBJECT_MAPPER.writeValueAsString(parameter);
        } catch (JsonProcessingException e) {
            throw new SQLException("Error converting List to JSON", e);
        }
        ps.setString(i, jsonStr);
    }

    @Override
    public List<String> getNullableResult(ResultSet rs, String columnName) throws SQLException {
        return parseJson(rs.getString(columnName));
    }

    @Override
    public List<String> getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
        return parseJson(rs.getString(columnIndex));
    }

    @Override
    public List<String> getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
        return parseJson(cs.getString(columnIndex));
    }

    private List<String> parseJson(String json) throws SQLException {
        if (json == null || json.trim().isEmpty()) {
            return null;
        }
        try {
            return OBJECT_MAPPER.readValue(json, new TypeReference<List<String>>() {});
        } catch (JsonProcessingException e) {
            throw new SQLException("Error parsing JSON: " + json, e);
        }
    }
} 